v. ill. 22-31 cm.
Topic: Student publications.
Work on the MSFC emulsion laboratory microscopes in which mechanical modifications previously made were verified is reviewed, as is a design study of a large area hybrid electronic/emulsion chamber balloon flight detector system. This design is built upon the experience obtained with the highly successful MSFC/UAH hybrid instrument flown by the JACEE consortium. The design included overall system design and specification, design and fabrication of a prototype large light diffusion for Cerenkov...
Topics: NASA Technical Reports Server (NTRS), CERENKOV COUNTERS, CERENKOV RADIATION, COSMIC RAYS,...
In January 1986, Voyager 2 took a series of pictures of Uranus and its satellites with the Imaging Science System (ISS) on board the spacecraft. Based on six stereo images from the ISS narrow-angle camera, a topographic map was compiled of the Southern Hemisphere of Miranda, one of Uranus' moons. Assuming a spherical figure, a 20-km surface relief is shown on the map. With three additional images from the ISS wide-angle camera, a control network of Miranda's Southern Hemisphere was established...
Topics: NASA Technical Reports Server (NTRS), IMAGING TECHNIQUES, PHOTOGRAMMETRY, SATELLITE IMAGERY, URANUS...
It is generally believed that convective motions below the solar photosphere induce a twist in the coronal magnetic field as a result of frozen-in physics. A question of interest is how much twist can one expect from a persistent convective motion, given the fact that dissipative effects will eventually figure. This question is examined by considering a model problem: two conducting plates, with finite resistivity, are set in sheared motion and forced at constant relative speed. A resistive...
Topics: NASA Technical Reports Server (NTRS), CONVECTIVE FLOW, MAGNETIC FIELDS, PHOTOSPHERE, SOLAR CORONA,...
A Ku-band IMPATT oscillator with two distinct output power ports was injection-locked alternately at both ports. The transmission locking bandwidth was nearly the same for either port. The lower free running power port had a reflection locking bandwidth that was narrower than its transmission locking one. Just the opposite was found at the other port. A detailed analytical model for two-port injection-locked oscillators is presented, and its results agree quite well with the experiments. A...
Topics: NASA Technical Reports Server (NTRS), INJECTION LOCKING, MATHEMATICAL MODELS, NUMERICAL ANALYSIS,...
Various architectures and their respective software for Hierarchically Intelligent Robots are discussed. They conform to the Principle of Increasing Precision with Decreasing Intelligence by following a three-level structure. The architecture of the organization and coordination levels is presented here and their algorithms are outlined.
Topics: NASA Technical Reports Server (NTRS), ARCHITECTURE (COMPUTERS), ARTIFICIAL INTELLIGENCE, DECISION...
Proper acoustic excitation of a single large-eddy break-up device can increase the resulting drag reduction and, after approximately 40 to 50 delta downstream, provide net drag reduction. Precise optimization of the input time delay, amplitude and response threshold is difficult but possible to achieve. Drag reduction is improved with optimized conditions. The possibility of optimized processing strongly suggests a mechanism which involves interaction of the acoustic waves and large eddies at...
Topics: NASA Technical Reports Server (NTRS), ACOUSTIC EXCITATION, AUGMENTATION, DRAG REDUCTION, VISCOUS...
Component assembly on printed circuitry keeps making giant strides toward denser packaging and smaller dimensions. From a single layer to multilayer, from through holes to surface mounted components and tape applied bonds, unrelenting progress results in new, difficult problems in assembling, soldering, inspecting and controlling the manufacturing process of the new electronics. Among the major problems are the variables introduced by human operators. The small dimensions and the tight assembly...
Topics: NASA Technical Reports Server (NTRS), INSPECTION, LASER OUTPUTS, LASER WELDING, PRINTED CIRCUITS,...
Thermocycling of ceramic-coated turbomachine components produces high thermomechanical stresses that are mitigated by plasticity and creep but aggravated by oxidation, with residual stresses exacerbated by all three. These residual stresses, coupled with the thermocyclic loading, lead to high compressive stresses that cause the coating to spall. A ceramic-coated gas path seal is modeled with consideration given to creep, plasticity, and oxidation. The resulting stresses and possible failure...
Topics: NASA Technical Reports Server (NTRS), CERAMICS, CREEP PROPERTIES, ENGINE PARTS, FAILURE MODES,...
The Fault Tree Compiler Program is a new reliability tool used to predict the top event probability for a fault tree. Five different gate types are allowed in the fault tree: AND, OR, EXCLUSIVE OR, INVERT, and M OF N gates. The high level input language is easy to understand and use when describing the system tree. In addition, the use of the hierarchical fault tree capability can simplify the tree description and decrease program execution time. The current solution technique provides an...
Topics: NASA Technical Reports Server (NTRS), COMPILERS, FAULT TOLERANCE, FAULT TREES, PROBLEM SOLVING,...
In recent years, interest in large deployable space antennae has led to the development of the 15 meter hoop/column antenna. The thermal environment the antenna is expected to experience during orbit is examined and the temperature distributions leading to reflector surface distortion errors are determined. Two flight orientations corresponding to: (1) normal operation, and (2) use in a Shuttle-attached flight experiment are examined. A reduced element model was used to determine element...
Topics: NASA Technical Reports Server (NTRS), HOOP COLUMN ANTENNAS, LARGE SPACE STRUCTURES, REFLECTOR...
Sources of internal gravity waves (IGW) in the upper atmosphere are assumed to be meteorological processes in the troposphere. These sources are vertically and horizontally inhomogeneous and time dependent. In order to describe the IGW propagation from such sources, a numerical solution of a system of hydrodynamical equations is required. In addition, it is necessary to take into account the influence of the altitude latitude inhomogeneity of the temperature and wind fields on the IGW...
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, GRAVITY WAVES, INTERNAL WAVES, MATHEMATICAL...
This study compares flare source volumes inferred from impulsive hard X-rays and microwaves with those derived from density sensitive soft X-ray line ratios in the O VII spectrum. The data for this study were obtained with the SMM Hard X-Ray Burst Spectrometer, Earth-based radio observatories, and the SOLEX-B spectrometer on the P78-1 satellite. Data were available for the flares of 1980 April 8, 1980 May 9, and 1981 February 26. The hard X-ray/microwave source volume is determined under the...
Topics: NASA Technical Reports Server (NTRS), IMPULSES, MICROWAVE EMISSION, SOLAR FLARES, SOLAR RADIATION,...
Orbit Transfer Vehicle (OTV) processing at the space station is divided into two major categories: OTV processing and assembly operations, and support operations. These categories are further subdivided into major functional areas to allow development of detailed OTV processing procedures and timelines. These procedures and timelines are used to derive the specific space station accommodations necessary to support OTV activities. The overall objective is to limit impact on OTV processing...
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, ORBIT TRANSFER VEHICLES, ORBITAL ASSEMBLY,...
Afghan refugees in Peshawar pakistan.
Afghan refugees in Peshawar pakistan.
Afghan refugees in Peshawar pakistan.
View of Afghan refugees in Peshawar Pakistan.
Afghan refugees in Peshawar pakistan.
Destruction of houses by Soviet bombardment, unexploded hand grenade, and Muj military activities in Kunar Province in June 1987
Agriculture and social life: farmer plowing his land by oxen, pastor safeguarding his sheep in Herat province in June 1987
View of Jam minarets, Soviet armored tank damaged by Muj and Muj activities in Herat province in June 1987
Commander Mulla Naqibullah with his Muj, prisoners of war and usage of BM-12 and Cannon by Muj in Kandahar Province in July 1987
Commander Mulla Naqibullah with his Muj, prisoners of war and usage of BM-12 and Cannon by Muj in Kandahar Province in July 1987
Commander Mulla Naqibullah, distruction of homes by Soviet bombardment, body of Kaubl regime's soldiers in Kandahar Province in July 1987
Commander Mulla Naqibullah with his Muj, prisoners of war and usage of BM-12 and Cannon by Muj in Kandahar Province in July 1987
Destruction of houses, gardens and mosque in Logar province in July 1987
Soviet bombardment, destruction and casualties in Logar province in July 1987
Social life of Muj and common people in Logar provice in July 1987
Professor Mujadidi and Mavlavi Muhammadi Press conference in Peshawar, Pakistan in July, 1987
Professor Mujadidi and Mavlavi Muhammadi Press conference in Peshawar, Pakistan in July, 1987
Refugees situation, Afghan refugees students (girls and boys) studying in Afghan schools in Quetta, pakistan in July 1987
Destroyed houses, gardens by Soviet bombardment, Soviet armour vehicle burnt by Muj inside Noristan, Kunar province in July 1987
Refugees situation, Afghan refugees students (girls and boys) studying in Afghan schools in Quetta, pakistan in July 1987
Refugees situation, Afghan refugees students (girls and boys) studying in Afghan schools in Quetta, pakistan in July 1987
Butterfly explosive devices dropped by Soviet, usage of 82mm cannon by Muj and destruction of Soviet vehicles in Ghazni province in July 1987
Butterfly explosive devices dropped by Soviet, usage of 82mm cannon by Muj and destruction of Soviet vehicles in Ghazni province in July 1987
Butterfly explosive devices dropped by Soviet, usage of 82mm cannon by Muj and destruction of Soviet vehicles in Ghazni province in July 1987
Butterfly explosive devices dropped by Soviet, usage of 82mm cannon by Muj and destruction of Soviet vehicles in Ghazni province in July 1987
Muj installing flags on graves, armed Muj praying for the soul of martyred and a Muj fired RPG-7.
Educational issues, students reading different mottos educational activities of teachers and students in Logar province in October 1987
Educational issues, different written mottos and teachers and students educational activities in Logar province in October 1987
Educational issue, children learning religious lesson from Mulla, social life of Kandahar residents and Muj activities in Kandahar province in October 1987
Pieces of Napalm bomb dropped by Soviet, Muj social life activities, and fruit seller selling watermelon in Kandahar province in October 1987
Educational issues, students reading different mottos educational activities of teachers and students in Logar province in October 1987
Pieces of Napalm bomb dropped by Soviet, Muj social life activities, and fruit seller selling watermelon in Kandahar province in October 1987
